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Wyszukujesz frazę "Wang, L" wg kryterium: Autor


Tytuł:
Hybrid modelling and performance evaluation of switched discrete-event systems
Autorzy:
Wang, L.
Powiązania:
https://bibliotekanauki.pl/articles/970351.pdf
Data publikacji:
2004
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
układ zespolony
układ komutowany
modelowanie hybrydowe
zachowanie okresowe
ocena działania systemu
complex systems
switched systems
discrete event systems
max-plus algebra
hybrid modelling
periodic behavior
performance evaluation
Opis:
Motivated by the integrated complexity of real-time intelligent control and optimization of industrial/manufacturing processes, this paper discusses hybrid modelling and asymptotic periodic behavior of a class of switched discrete event systems, and shows how to evaluate the asymptotic performance/efficiency of such systems. We prove that, under some mild conditions, the switched discrete event system will achieve asymptotic periodic dynamics, and its performance/efficiency can be evaluated by calculating the eigenvalue of certain matrix in max-plus algebra. Illustrative examples are provided.
Źródło:
Control and Cybernetics; 2004, 33, 2; 311-321
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Robust performance of a class of control systems
Autorzy:
Wang, L.
Powiązania:
https://bibliotekanauki.pl/articles/970421.pdf
Data publikacji:
2004
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
system niepewny
analiza odporności
stabilność Hurwitza
D-stabilność
funkcja przenoszenia
uncertain systems
robustness analysis
Kharitonov's theorem
complex interval polynomials
polynomial matrix family
Hurwitz stability
D-stability
transfer functions
strict positive realness
Opis:
Some Kharitonov-like robust Hurwitz stability criteria are established for a class of complex polynomial families with nonlinearly correlated perturbations. These results are extended to the polynomial matrix case and non-interval D-stability case. Applications of these results in testing of robust strict positive realness of real and complex interval transfer function families are also presented.
Źródło:
Control and Cybernetics; 2004, 33, 1; 71-83
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Positivity and stabilization of driver support systems
Autorzy:
Wang, L.
Ackermann, J.
Powiązania:
https://bibliotekanauki.pl/articles/206824.pdf
Data publikacji:
1999
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
dodatniość
parametry niepewne
stabilność
sterowanie
driver support systems
PID controllers
positivity
stabilization
unceratin parameters
Opis:
In this paper, we first show that the transfer function from the front steering angle to yaw rate is strictly positive real, irrespective of the uncertain mass and unceratin velocity. We then show how to determine the positivity margin for this transfer function. Some stabilization results are obtained. Finally, we show how to check the positivity of a controller family.
Źródło:
Control and Cybernetics; 1999, 28, 1; 53-59
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Rheological Properties and Water-in-Oil Structural Stability of Emulsion Matrixes
Autorzy:
Wang, L.
Fang, J.
Powiązania:
https://bibliotekanauki.pl/articles/357954.pdf
Data publikacji:
2013
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Przemysłu Organicznego
Tematy:
emulsifier
emulsion matrix
rheological properties
viscoelasticity
water-in-oil structural stability
Opis:
The emulsion explosive is one of the important industrial explosives.The structural stability of the water-in-oil (W/O) emulsion matrix of an emulsion ex plosive determines the reliability of its initiation, safety and detonation performance. It is known that the emulsifier is one of the most important factors affecting W/O structural stability. In this paper, several emulsifiers with the functionalities of imide, amide, ester, salt, and sorbin monooleate (SMO) were selected. From the perspective of the rheological properties, the effects of the emulsifier structure and its functionality on the viscosity and visco-elastic properties of the emulsion matrix were analyzed and researched. The results show that emulsifiers with imide/amide functionality and their corresponding emulsion matrixes have higher viscosity at normal temperatures and better fluidity at high temperatures than those of the others. The linear visco-elastic region (LVR) for emulsion matrixes containing these emulsifiers is wider than that of the others. The effect of a change in ambient temperature on the viscosity for a complex emulsifier is small. The emulsion matrix containing the emulsifier named LZ2727B is the most stable, followed by the emulsifier named LZ2727D. This conclusion is consistent with the conclusions from tension tests and from high and low temperature cycling experiments. From the emulsifiers studied in this paper, LZ2727B and LZ2727D emulsifiers are very suitable for manufacturing packaged emulsion explosives. On the other hand emulsifiers based on SMO functionalities, named LZ2731 and LZ2735, are the best choices for manufacturing bulk emulsion explosives.
Źródło:
Central European Journal of Energetic Materials; 2013, 10, 1; 87-102
1733-7178
Pojawia się w:
Central European Journal of Energetic Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Minimum dispersion coefficient criteria based positioning algorithm for BDS
Autorzy:
Wang, L.
Li, L.
Powiązania:
https://bibliotekanauki.pl/articles/141700.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
alpha-stable distribution
BeiDou satellites
Kalman filter
minimum dispersion coefficient criteria
non-Gaussian noise
positioning algorithm
Opis:
The BeiDou navigation satellite system (BDS) is one of the four global navigation satellite systems. More attention has been paid to the positioning algorithm of the BDS. Based on the study on the Kalman filter (KF) algorithm, this paper proposed a novel algorithm for the BDS, named as the minimum dispersion coefficient criteria Kalman filter (MDCCKF) positioning algorithm. The MDCCKF algorithm adopts minimum dispersion coefficient criteria (MDCC) to remove the influence of noise with an alpha-stable distribution (ASD) model which can describe non-Gaussian noise effectively, especially for the pulse noise in positioning. By minimizing the dispersion coefficient of the positioning error, the MDCCKF assures positioning accuracy under both Gaussian and non-Gaussian environment. Compared with the original KF algorithm, it is shown that the MDCCKF algorithm has higher positioning accuracy and robustness. The MDCCKF algorithm provides insightful results for potential future research.
Źródło:
Archives of Electrical Engineering; 2018, 67, 4; 739-753
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimal control of constrained delay-differential inclusions with multivalued initial conditions
Autorzy:
Mordukhovich, B. S.
Wang, L.
Powiązania:
https://bibliotekanauki.pl/articles/970519.pdf
Data publikacji:
2003
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
aproksymacja dyskretna
warunek konieczny optymalności
analiza wariacyjna
stabilność
optymalizacja niegładka
różniczkowanie uogólnione
delay-differential inclusions
discrete approximations
necessary optimality conditions
variational analysis
stability
nonsmooth optimization
generalized differentiation
Opis:
This paper studies a general optimal control problem for nonconvex delay-differential inclusions with endpoint constraints. In contrast to previous publications on this topic, we incorporate time-dependent set constraints on the initial interval, which are specific for systems with delays and provide an additional source for optimization. Our variational analysis is based on well-posed discrete approximations of constrained delay-differential inclusions by a family of time-delayed systems with discrete dynamics and perturbed constraints. Using convergence results for discrete approximations and advanced tools of nonsmooth variational analysis, we derive necessary optimality conditions for constrained delay-differential inclusions in both Euler-Lagrange and Hamiltonian forms involving nonconvex generalized differential constructions for nonsmooth functions, sets, and set-valued mappings.
Źródło:
Control and Cybernetics; 2003, 32, 3; 585-609
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Thermal effect on damaged stay-cables
Autorzy:
Wang, L.
Wu, Y.
Wang, D.
Powiązania:
https://bibliotekanauki.pl/articles/280543.pdf
Data publikacji:
2014
Wydawca:
Polskie Towarzystwo Mechaniki Teoretycznej i Stosowanej
Tematy:
stay cables
damage
thermal effect
aspect ratio
Opis:
Cables may suffer severe damage in cable-stayed bridges, leading to cable relaxation and tension loss. Such a damage effect merges in the sag augmentation or tension tightened by the thermal effect. This paper is intended to investigate the static response of damaged cables coupled with the thermal effect. With the introduction of three damage parameters such as damage position, damage degree and damage range as well as temperature parameter, the dimensionless governing equations for cables are derived and the numerical method is employed to solve the nonlinear equations. The static behavior of damaged cables due to the thermal coupling effect is analyzed, and the way to remove the thermal effect is given. It shows that the aspect ratio is the major factor is the deflection of the mid-span and horizontal force in the cable, whereas the angle inclination is the next important parameter. Cables with the natural length close to the chord distance reveal the highest sensitivity to temperature, whereas pre-tensioned and non-pre-tensioned cables are less sensitive to the thermal effect. It further demonstrates that with more damage included, the sensitive scope of the variation coefficient of the axial force with aspect ratio and temperature changes dramatically.
Źródło:
Journal of Theoretical and Applied Mechanics; 2014, 52, 4; 1071-1082
1429-2955
Pojawia się w:
Journal of Theoretical and Applied Mechanics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Evolution of hierarchical structure and spatial pattern of coastal cities in China – based on the data of distribution of marine-related enterprises
Autorzy:
Wang, L.
Xiao, W.
Wang, C.
Powiązania:
https://bibliotekanauki.pl/articles/258846.pdf
Data publikacji:
2017
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
hierarchical structure
spatial pattern
city network
Opis:
In this paper, a comprehensive research of the evolution of the hierarchical structure and spatial pattern of coastal cities in China was conducted based on the data of distribution of the headquarters and subsidiaries of marine-related enterprises in 1995, 2005 and 2015 using the city network research method proposed by Taylor. The results of the empirical research showed: China’s coastal city network had an obvious hierarchical characteristics of “national coastal cityregional coastal city-sub-regional coastal city-local coastal city”, in the 20 years of development process, the hierarchies of coastal cities in China showed a hierarchical progressive evolution; in past 20 years, the spatial pattern and network structure of coastal cities in China tended to be complete, and the city network was more uniform, forming a “three tiers and three urban agglomerations” network structure; the strength of connection among the cities was obviously strengthened, and the efficiency of urban spatial connection was improved overall.
Źródło:
Polish Maritime Research; 2017, S 3; 58-64
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Efficacy evaluation of two live virus vaccines against an emerging pseudorabies virus variant
Autorzy:
Wang, M.
Wang, L.
Zhao, Q.
Powiązania:
https://bibliotekanauki.pl/articles/2087402.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
pseudorabies virus (PRV)
variant TJ
live virus vaccines
cross-protection
Źródło:
Polish Journal of Veterinary Sciences; 2019, 4; 639-645
1505-1773
Pojawia się w:
Polish Journal of Veterinary Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Physiological acclimation of Dicranostigma henanensis to soil drought stress and rewatering
Autorzy:
Wang, N.
Chen, H.
Wang, L.
Powiązania:
https://bibliotekanauki.pl/articles/2130560.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Botaniczne
Tematy:
Dicranostigma henanensis
drought stress
physiological changes
photosynthesis
rewatering
Opis:
e adaptability of plants to drought not only includes their ability to resist drought stress, but also their ability to recover aer stress is relieved. In this study, a weighting method was used to control the soil water content to produce a soil water stress gradient. e effects of drought and rewatering on the changes in osmotic adjustment substance content, antioxidant enzyme activity, and photosynthetic characteristics of potted Dicranostigma henanensis seedlings were measured on Day 28 aer the imposition of watering treatments and Day 7 aer rewatering. During the drought stress process, the relative electrical conductivity, thiobarbituric acid, water use efficiency, and proline content displayed a continuously increasing trend. Further, the net photosynthetic rate, stomatal conductance, and transpiration rate constantly decreased, while the chlorophyll content first increased and then decreased. Aer rehydration, superoxide dismutase (EC 1.15.1.1) activity and photosynthetic parameters quickly recovered to the CK level (soil moisture is 75%–80% of the maximum water holding capacity in the field), indicating that D. henanensis plants have a strong ability to repair the damage caused by drought stress. In particular, the photosynthetic machinery may have sophisticated regulation and repair mechanisms, which may be associated with its stable photosystem. Collectively, our findings demonstrate that the D. henanensis plant has a strong ability to adapt to arid environments, and therefore could be an excellent ornamental flower for landscaping in arid and semiarid areas.
Źródło:
Acta Societatis Botanicorum Poloniae; 2021, 90
0001-6977
2083-9480
Pojawia się w:
Acta Societatis Botanicorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Construction method of the topographical features model for underwater terrain navigation
Autorzy:
Wang, L.
Yu, L.
Zhu, Y.
Powiązania:
https://bibliotekanauki.pl/articles/259976.pdf
Data publikacji:
2015
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
Terrain Aided Navigation
terrain features
Terrain Navigation Information Content (TNIC)
correlation
Opis:
Terrain database is the reference basic for autonomous underwater vehicle (AUV) to implement underwater terrain navigation (UTN) functions, and is the important part of building topographical features model for UTN. To investigate the feasibility and correlation of a variety of terrain parameters as terrain navigation information metrics, this paper described and analyzed the underwater terrain features and topography parameters calculation method. Proposing a comprehensive evaluation method for terrain navigation information, and constructing an underwater navigation information analysis model, which is associated with topographic features. Simulation results show that the underwater terrain features, are associated with UTN information directly or indirectly, also affect the terrain matching capture probability and the positioning accuracy directly.
Źródło:
Polish Maritime Research; 2015, S 1; 121-125
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An Improved Method of Permutation Correction in Convolutive Blind Source Separation
Autorzy:
Wang, L.
Ding, H.
Yin, F.
Powiązania:
https://bibliotekanauki.pl/articles/177954.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
blind source separation
cocktail party
convolutive mixing
frequency domain
permutation problem
Opis:
This paper proposes an improved method of solving the permutation problem inherent in frequency-domain of convolutive blind source separation (BSS). It combines a novel inter-frequency dependence measure: the power ratio of separated signals, and a simple but effective bin-wise permutation alignment scheme. The proposed method is easy to implement and surpasses the conventional ones. Simulations have shown that it can provide an almost ideal solution of the permutation problem for a case where two or three sources were mixed in a room with a reverberation time of 130 ms.
Źródło:
Archives of Acoustics; 2010, 35, 4; 493-504
0137-5075
Pojawia się w:
Archives of Acoustics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Computational fluid dynamics (CFD) numerical simulation and particle image velocimetry (PIV) measurement of a packed flotation column
Autorzy:
Yan, X.
Chen, Z.
Wang, L.
Powiązania:
https://bibliotekanauki.pl/articles/110183.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
cyclonic-static microbubble flotation column
computational fluid dynamics
sieve-plate packing
particle image velocimetry
velocity distribution
Opis:
Packing is a useful method to obtain a static separation environment for a high flotation recovery and selectivity. In this study, the single-phase flow field in a packed lab-scale cyclonic-static microbubble flotation column (FCSMC) was investigated by computational fluid dynamics (CFD) simulation. Turbulence model was verified by Particle Image Velocimetry (PIV) experiment; the simulation results obtained by the RSM (Reynolds Stress Model) are closer to the experimental data. Based on this validation, RSM turbulence model was used to obtain the effect of sieve-plate on the hydrodynamic characteristics in the column flotation zone. The results show that the sieve-plate packing arrangement greatly straightens the rotation flow and decreases the turbulence. To further improve the effect of packing, two layers of sieve plates were used, and one diameter (1D = 190 mm) was selected as the reasonable distance between the two layers of sieve plates. To quantitative evaluate the effect of sieve-plate packing, the logarithm of Pdk over the logarithm of Pdo was calculated based on the volume-averaged turbulence dissipation rate, increasing from 24.72 for one layer of sieve-plate packing to 216.96 for two layers of sieve-plate packing. The probability of detachment significantly decreased for two layers of sieve-plate packing, and the recovery efficiency was significantly improved.
Źródło:
Physicochemical Problems of Mineral Processing; 2018, 54, 2; 395-405
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study on self-repairing and non-diffraction of Airy beams in slant atmospheric turbulence
Autorzy:
Li, Y.-Q.
Wang, L.-G.
Powiązania:
https://bibliotekanauki.pl/articles/174867.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
atmospheric turbulence
Airy beam
self-repairing
non-diffraction
numerical simulation
Opis:
The Airy beams propagation in atmospheric turbulence along a slant path was simulated numerically, based on the split-step Fourier method. Also, the self-repairing and non-diffraction characteristics of Airy beams were investigated and compared with beams propagation on a horizontal path. The effects of parameters including zenith angle, propagation distance, radii of Gaussian aperture and turbulence intensity on the two characteristics of beams were revealed. Additionally, the two characteristics of the Airy beam were compared with those of a Bessel–Gauss beam. The results showed that the two beams obscured by Gaussian apertures can be repaired after propagating some distance along a slant path. However, the non-diffraction characteristic of an Airy beam was stronger than that of a Bessel–Gauss beam and the amplitude attenuation rate of the Bessel–Gauss beam was greater than that of the Airy beam in the process of self-repairing. Results obtained can provide a theoretical basis for an outdoor experiment as well as theoretical guidance for various practical applications including laser communications, laser warning systems, and remote sensing.
Źródło:
Optica Applicata; 2018, 48, 3; 435-447
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Robust stability of a family of matrices
Autorzy:
Wang, L.
Zhang, L.
Wang, Z.
Powiązania:
https://bibliotekanauki.pl/articles/205534.pdf
Data publikacji:
2001
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
rezultat wierzchołkowy
rodzina macierzy
stabilność odporności
struktura wieloliniowej niepewności
teoria algebry
algebra theory
matrix families
multilinear uncertainty structure
robust stability
vertex results
Opis:
For a family of matrices with multilinear uncertainty structure, stability of the entire matrix family can be guaranteed by stability of its vertex matrices.
Źródło:
Control and Cybernetics; 2001, 30, 3; 331-337
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the number of positive solutions to a class of integral equations
Autorzy:
Wang, L.
Yu, W.
Zhang, L.
Powiązania:
https://bibliotekanauki.pl/articles/206271.pdf
Data publikacji:
2003
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
równanie całkowe
rozwiązanie dodatnie
integral equations
positive solutions
complete discrimination system for polynomials
number of solutions
Opis:
By using the complete discrimination system for polynomials, we study the number of positive solutions in C[0,1] to the integral equation phi(x) = integral[...] k(x,y)phi^n(y)dy, where k(x,y) = phi1(x)phi1(y)+phi2(x)phi2(y),[phi]i(x) > 0,[phi]i(y) > 0,0 < x,y < 1,i = 1,2, are continuous functions on [0,1], n is a positive integer. We prove the following results: when n = 1, either there does not exist, or there exist infinitely many positive solutions in C[0,1]; when n [is greater than or equal] 2, there exist at least 1, at most n + 1 positive solutions in C[0,1]. Necessary and sufficient conditions are derived for the cases: 1) n = 1, there exist positive solutions; 2) n [is greater than or equal to] 2, there exist exactly m (m belongs to {1,2,..., n + 1}) positive solutions. Our results generalize the ones existing in the literature, and their usefulness is shown by examples.
Źródło:
Control and Cybernetics; 2003, 32, 2; 383-395
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Numerical investigation of the two-dimensional gas temperature distribution based on tunable diode laser absorption spectroscopy
Autorzy:
Shao, J
Wang, L
Ying, C
Powiązania:
https://bibliotekanauki.pl/articles/174322.pdf
Data publikacji:
2015
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
tomographic
modified adaptive algebraic reconstruction technique (MAART)
tunable diode laser absorption spectroscopy (TDLAS)
Opis:
Based on tunable diode laser absorption spectroscopy and modified adaptive algebraic reconstruction technique, two-dimensional tomographic reconstruction was derived for the gas temperature distribution in the range of 600–1400 K in the controlled projections. It is explicitly shown that the quality of temperature reconstruction is heavily dependent on the relative sensitivity of the selected spectrum and the algorithm of modified adaptive algebraic reconstruction technique but independent of the complexity of the present field distribution. When the relative sensitivity is less than 1.5, the accuracy of reconstruction relates to the relative sensitivity of the selected spectrum and improves with the increase in relative sensitivity. When the relative sensitivity is larger than 1.5, the accuracy is mainly limited by the algorithm of modified adaptive algebraic reconstruction technique.
Źródło:
Optica Applicata; 2015, 45, 2; 183-198
0078-5466
1899-7015
Pojawia się w:
Optica Applicata
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cold rolling mill thickness control using the cascade-correlation neural network
Autorzy:
Frayman, Y.
Wang, L.
Wan, C.
Powiązania:
https://bibliotekanauki.pl/articles/206844.pdf
Data publikacji:
2002
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
konstrukcja dynamicznej sieci neuronowej
sieć neuronowa kaskadowo-korelacyjna
sterowanie grubością walcowni zimnej
cascade-correlation neural network
cold rolling mill thickness control
direct MRAC
dynamic neural network construction
Opis:
The improvements in thickness accuracy of a steel strip produced by a tandem cold-rolling mill are of substantial interest to the steel industry. In this paper, we designed a direct model-reference adaptive control (MRAC) scheme that exploits the natural level of excitation existing in the closed-loop with a dynamically constructed cascade-correlation neural network (CCNN) as a controller for cold rolling mill thickness control. Simulation results show that the combination of a such a direct MRAC scheme and the dynamically constructed CCNN significantly improves the thickness accuracy in the presence of disturbances and noise in comparison with to the conventional PID controllers.
Źródło:
Control and Cybernetics; 2002, 31, 2; 327-342
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Marine industrial cluster structure and its coupling relationship with urban development: a case of Shandong province
Autorzy:
Xiao, W.
Zhao, B.
Wang, L.
Powiązania:
https://bibliotekanauki.pl/articles/259796.pdf
Data publikacji:
2016
Wydawca:
Politechnika Gdańska. Wydział Inżynierii Mechanicznej i Okrętownictwa
Tematy:
marine industry
industrial cluster
urban development
coupling coordination model
Opis:
Marine economy is a new economic form, emphasizing new development concept, new operation mechanism and management mode. In recent years, marine economy shows rapid growth, and marine industry presents a clustering development trend. The industrial linkage effect, industrial agglomeration effect and industrial radiation effect of the marine industrial cluster are important motive forces for the development of coastal cities. The marine industrial cluster takes coastal cities as the development platform and space, while the coastal cities achieve rapid and sustainable development based on the marine industrial cluster. The synergetic and coupling development of the marine industrial cluster and coastal cities is an important way for the promotion of industrial competitiveness and urban competitiveness. This paper developed a measure to identify the marine industrial cluster, designed the evaluation index of coupling of marine industrial cluster and coastal cities development from two perspectives of industrial linkage and spatial agglomeration, taking Shandong province, a typical coastal province in China, as an example, it studied the situation of the marine industrial cluster based on input-output data and data of marine enterprises of coastal cities, based on which it explored the coupling relationship between marine industrial cluster and coastal cities of Shandong province.
Źródło:
Polish Maritime Research; 2016, S 1; 115-122
1233-2585
Pojawia się w:
Polish Maritime Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimal control of delay-differential inclusions with multivalued initial conditions in infinite dimensions
Autorzy:
Mordukhovich, B. S.
Wang, D.
Wang, L.
Powiązania:
https://bibliotekanauki.pl/articles/969562.pdf
Data publikacji:
2008
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
discrete approximations
optimal control
variational analysis
endpoint constraints
delay-differential inclusions
multivalued initial conditions
extended Euler-Lagrange formalism
generalized differentiation
Banach and Asplund spaces
necessary optimality conditions
Opis:
This paper is devoted to the study of a general class of optimal control problems described by delay-differential inclusions with infinite-dimensional state spaces, endpoints constraints, and multivalued initial conditions. To the best of our knowledge, problems of this type have not been considered in the literature, except for some particular cases when either the state space is finite-dimensional or there is no delay in the dynamics. We develop the method of discrete approximations to derive necessary optimality conditions in the extended Euler-Lagrange form by using advanced tools of variational analysis and generalized differentiation in infinite dimensions. This method consists of the three major parts: (a) constructing a well-posed sequence of discrete-time problems that approximate in an appropriate sense the original continuous-time problem of dynamic optimization; (b) deriving necessary optimality conditions for the approximating discrete-time problems by reducing them to infinite-dimensional problems of mathematical programming and employing then generalized differential calculus; (c) passing finally to the limit in the obtained results for discrete approximations to establish necessary conditions for the given optimal solutions to the original problem. This method is fully realized in the delay-differential systems under consideration.
Źródło:
Control and Cybernetics; 2008, 37, 2; 393-428
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Carbon-based acid catalyst from waste seed shells: preparation and characterization
Autorzy:
Wang, L. H.
Liu, H.
Li, L.
Powiązania:
https://bibliotekanauki.pl/articles/778575.pdf
Data publikacji:
2015
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
carbon-based solid acid
waste seed shells
esterification
transesterification
biodiesel
Opis:
A carbon-based solid acid catalyst was prepared by the sulfonation of carbonized seed shells of Jatropha curcas (J. curcas L.). The structure of amorphous carbon consisting of polycyclic aromatic carbon sheets attached a high density of acidic SO3H groups (2.0 mmol · g−1) was identified with scanning electron microscopy (SEM), fourier transform infrared (FTIR) spectroscopy, powder X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The performance of the solid acid catalyst was evaluated for biodiesel production in the esterification of oleic acid with methanol. 95.7% yield of biodiesel was obtained after 2 h reaction and the conversions with reused catalyst varied in the range of 95.7% to 95.1%, showing better activity and stability than commercial catalyst amberlyst-46. It was also observed that the prepared catalyst showed enhanced activity in the transesterification of triolein with methanol when compared with other solid acid catalysts. A synergistic effect results from the high density of SO3H groups and the good access of reactants to the acidic sites can be used to explain the excellent catalytic activity, as well as the strong affinity between the hydrophilic reactants and the neutral OH groups bonded to the polycyclic aromatic carbon rings.
Źródło:
Polish Journal of Chemical Technology; 2015, 17, 4; 37-41
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Algorytm do oceny i analizy stacjonarnej dostępności operacyjnej oparty na specyfikacji wymagań
An algorithm for evaluation and analysis of stationary operational availability basing on mission requirements
Autorzy:
Wang, N.
Kang, R.
Jia, Z.
Wang, L.
Powiązania:
https://bibliotekanauki.pl/articles/301045.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
dostępność operacyjna
stan stacjonarny
niezawodność
obsługiwalność
części zapasowe
operational availability
stationary state
reliability
maintainability
spare parts
Opis:
Zarówno metody matematyczne jak i symulacyjne mają ograniczenia jeśli chodzi o ocenę stacjonarnej dostępności operacyjnej. Te pierwsze zakładają, że popyt jest niezależny od systemu operacyjnego, co może skutkować niedoszacowaniem dostępności operacyjnej. Te drugie wymagają dużej liczby prób, aby uzyskać wyniki o wystarczającym stopniu ufności w warunkach wcześniej określonych scenariuszy. Niniejszy artykuł zajmuje się problemem określenia stacjonarnej dostępności operacyjnej na podstawie modeli matematycznych. Proponowany model bierze pod uwagę wiele czynników, wliczając w to pasywację systemu, specyfi kację wymagań, parametry projektowe systemu, liczbę działających systemów, czas realizacji oraz czas obsługi. Artykuł przedstawia metodę aproksymacji dostępności operacyjnej. Użyty przykład ilustruje związek pomiędzy wyżej wspomnianymi czynnikami. Doświadczenia numeryczne pokazują, że model ten jest zgodny z wynikami symulacji Monte Carlo, potwierdzając realność i racjonalność proponowanej metody.
Both mathematical and simulation methods have limitations for evaluation of stationary operational availability. The former assumes that demand is independent of the operating system, which can result in underestimation of the operational availability. The latter requires a large number of trials to obtain the results with a suffi cient degree of confi dence under the pre-specifi ed scenarios. This paper addresses the issue of determining the stationary operational availability based on mathematical models. The proposed model considers many factors including system passivation, mission requirements, system design parameters, the number of working systems, lead time, and maintenance time. An approximation method to the operational availability is given. Specifi c example is used to illustrate the relationship among the aforementioned factors. Numerical experiments show that the model agrees well with Monte Carlo simulation results and the feasibility and rationality of the proposed method are validated.
Źródło:
Eksploatacja i Niezawodność; 2010, 2; 31-35
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimising extended warranty policies following the two-dimensional warranty with repair time threshold
Optymalizacja polityki gwarancyjnej w okresie po wygaśnięciu dwuwymiarowej gwarancji z ustaloną górną granicą czasu naprawy
Autorzy:
Wang, L.
Pei, Z.
Zhu, H.
Liu, B.
Powiązania:
https://bibliotekanauki.pl/articles/301099.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
extended warranty
repair time threshold
two-dimensional warranty
renewing warranty
przedłużona gwarancja
górna granica czasu naprawy
gwarancja dwuwymiarowa
odnowienie gwarancji
Opis:
This paper considers an optimal extended warranty policies after the expiration of base two-dimensional warranty with repair time threshold. During the base two-dimensional warranty period, each failure of the equipment can be either replaced or minimally repaired depending on a pre-specified repair time threshold. After the base warranty expires, the length of an extended warranty policy is available for selection. The equipment is minimally repaired on each failure during the extended warranty. In this study, the length of the extended warranty period is optimized by minimizing the expected cost rate incurred over the whole warranty coverage, from the views of customs and manufacturers respectively. For the purpose of illustration, we present and discuss some numerical examples. The effect of repair time threshold on the optimal strategy is also investigated numerically.
W niniejszej pracy rozważano optymalną politykę przedłużania gwarancji po wygaśnięciu podstawowej gwarancji dwuwymiarowej z ustaloną górną granicą czasu naprawy. W podstawowym okresie obowiązywania gwarancji dwuwymiarowej, po każdej awarii urządzenie zostaje poddane minimalnej naprawie, lub – jeśli naprawa nie może być wykonana we wcześniej ustalonym czasie naprawy – wymienione. Po wygaśnięciu gwarancji podstawowej, konieczne jest wybranie długości okresu obowiązywania gwarancji rozszerzonej. Podczas trwania okresu gwarancji przedłużonej, sprzęt naprawia się w sposób minimalny (naprawa minimalna) po każdorazowym uszkodzeniu. W niniejszej pracy, optymalizowano długość przedłużonego okresu gwarancyjnego poprzez minimalizację oczekiwanych kosztów poniesionych podczas całego okresu trwania gwarancji; optymalizację przeprowadzono z perspektywy klienta jak i producenta . Dla ilustracji, przedstawiono i omówiono wybrane przykłady numeryczne. Przeprowadzono także analizę numeryczną wpływu górnej granicy czasu naprawy na optymalną strategię gwarancyjną.
Źródło:
Eksploatacja i Niezawodność; 2018, 20, 4; 523-530
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Antimicrobial properties of flax fibers in the enzyme retting process
Właściwości antybakteryjne lnu w procesie enzymatycznego roszenia
Autorzy:
Tian, Y.
Liu, X.
Zheng, X.
Wang, L.
Powiązania:
https://bibliotekanauki.pl/articles/231965.pdf
Data publikacji:
2016
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
Tematy:
flax fibre
pectic substance content
antibacterial property
retting
włókno lniane
substancja pektynowa
właściwości antybakteryjne
roszenie
Opis:
“GB/T 20944.3-2008--Part 3: Shake flask method” was applied to assess the antimicrobial property of flax fibres. The antimicrobial efficiency of flax fibre was represented as the absolute antimicrobial rate and relative antimicrobial rate. Cotton fibre served as a contrast in relation to the antimicrobial rate. The retted flax fibre showed an absolute antimicrobial rate against E.coli and S. aureus, but only presented a relative antimicrobial rate against S. cerevisiae. The contents of pectic substances of flax straw such as cerolipoid, hydrotrope, pectin, hemicellulose and lignin declined during flax retting, especially lignin, whose content declined from 24% to 7.13%, and gaps appeared between the fibre bundles. Consequently the antimicrobial efficiency of flax fibre decreased gradually. This experiment confirmed the existence of antibacterial substances, but exactly what compounds associated with flax exhibiting antimicrobial properties is not discussed.
Właściwości antybakteryjne włókien lnianych badano zgodnie z normą GB/T20944.32008: Właściwości oceniano poprzez bezwzględną i względną antybakteryjną intensywność. Włókna bawełniane służyły jako materiał porównawczy przy ocenianiu antybakteryjnej intensywności względnej. Roszone włókna lnu wykazywały bezwzględną intensywność antybakteryjną przeciwko E. coli i S. aureus, ale tylko względną intensywność antybakteryjną przeciwko S. cerevisiae. Zawartość substancji pektynowych w słomie lnianej, takich jak cerolipoidy, hydrotopy, pektyny, chemiceluloza, i ligniny zmniejszała się podczas roszenia. Szczególnie zmniejszyła się zawartość lignin spadając z 24% do 7,13%. W czasie roszenia pojawiały się szczeliny pomiędzy wiązkami włókien. W konsekwencji zdolności antybakteryjne włókien lnianych ulegały systematycznej degradacji. Przeprowadzony eksperyment potwierdził istnienie antybakteryjnych substancji ale nie stwierdzono, które składniki były najbardziej aktywne antybakteryjnie.
Źródło:
Fibres & Textiles in Eastern Europe; 2016, 1 (115); 15-17
1230-3666
2300-7354
Pojawia się w:
Fibres & Textiles in Eastern Europe
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Analytic Equation of State and Thermodynamic Properties, for α-, β-, and γ-Si₃N₄ Based on Analytic Mean Field Approach
Autorzy:
Wang, L.
Sun, J.
Yang, W.
Tian, R.
Powiązania:
https://bibliotekanauki.pl/articles/1812044.pdf
Data publikacji:
2008-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
64.10.+h
65.40.-b
61.66.Fn
Opis:
The analytic mean field potential approach is applied to α-, β-, and γ-Si₃N₄. The analytic expressions for the Helmholtz free energy, internal energy, and equation of state were derived. The formalism for the case of the Morse potential is used in this work. Its six potential parameters are determined through fitting the compression experimental data of α-, β-, and γ-Si₃N₄. The calculated compression curves of α-, β-, and γ-Si₃N₄ are in good agreement with the available experimental data. This suggests that the analytic mean field potential approach is a very useful approach to study the thermodynamic properties of Si₃N₄. Furthermore, we predict the variation of the free energy and internal energy with the molar volume at several higher temperatures and calculate the temperature dependence of the molar volume, bulk modulus, thermal expansion coefficient and isochoric heat capacity at zero pressure.
Źródło:
Acta Physica Polonica A; 2008, 114, 4; 807-818
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł

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